Johannes selwig



(No Modem I J- .SELWIG- NITRATING APPARATUS.

No. 541,573. Patented June 25, 1895,v

I I I JOHANNES SELWIG, OF BRUNSWICK, GERMANY, ASSIGNOR T O SELVIG inLANGE, SAME PLACE.

NITRATING APPARATUS.

SPECIFICATION forming part of Letters Patent No. 541,573, dated June 25,1895.

Application filed June 13, 189]. Serial No. 396,135. (No model.)Patented in Germany June 18,1891, No. 64,447; in England .Tune 24, 1891,No. 10,747, and in Switzerland, No, 3.862 M1891.-

To a-ZZ whom it may concern:

Beit known that I, JOHANNES SnLwrG, a subjectof the German Emperor,residing at Brunswick, Germany, have invented a Nitrating Apparatus,(which has been patented4 in Germany, No.,64c,447, dated June 18, 1891;in England, No.10,747, dated June 24, 1891, and in Switzerland, No.3,862 of 1891,) of which the following is a specification.

The invention relates to a new and useful nitrating apparatus forperforming the nitrating of cotton, straw and other solid substances,which was heretofore performed in the following manner: The substancewas nitrated in a nitrating vat of suitable shape filled with acid. Thenthe acid was removed as far as possible from the nitrated substance bythe latter being pressed out or the acid being sucked off. At last thesubstance was taken out of the apparatus and transported to acentrifugal machine in which it was freed from the excess of acid bycentrifugal force. The transport of the nitrated substance from thenitrating apparatus to the centrifugal is incommodious as Well asinjuriousto the workmen, the latter being always exposed to the noxiousvapors caused by the process.

The object of my invention is to avoid this transport. I attain this endby nitrating the substance and expelling the excess of acid from thenitrated substance by centrifugal force in one and the same apparatus,viz., in a centrifugal machine with perforated basket, the casing andbasket of which can be filled with the acid, for which purpose thecasing must be closed at the bottom and provided with a discharge cock.

The accompanying drawing is a vertical section of such a machine, whichI call nitrating centrifugal machine.

A is the perforated revolving basket of the machine surrounded by acylindrical wrought or cast iron casing B, the latter being perfectlyclosed below, when the discharge cock C is shut. The basket A is carriedby a castiron dome a upon a central shaft b arranged with driving pulleyc, footstep and neck bearing on the central bracket d whose upper edge elies over the surface s of the acid when the casing is filled, toprevent the corrosion of the neck bearing. The whole is supported by thelower cast iron part of the casing B, the bracket d forming the centralpart of its inclined bottomf. A cock C is fixed to the discharge spout gjoining the bottom f. For regulating the temperature of the acid duringthe nitrating the upper cylindrical part of the casing B is furnishedwith a jacket h, through which cold or hot water or any other uidcirculates, when required; i being the ad missiontap and pipe, 7c theoverflow-pipe of the fluid. The jacket h can be replaced by a coiledtube ora tube of anyother shape placed in the casing through lwhich thesaid fluid flows during the nitrating.

On the top the casing B carries an annular rim Z which prevents thesubstance to be nitrated from entering the annular space surrounding thebasket A, when charging the latter. Above the casing a head-piece D isarranged similar to the fume-hoods used in chemical laboratories,provided with a door m, the upper eduction pipe not the head-piece beingconnected with an exhauster, which draws off the noxious vapors causedby the process. The pipe o joining the rim Z, which is also connectedwith the exhauster serves the Vsame purpose. lo is the'inlet-pipe forthe acid communicating through three taps q q2 g3 with acid tanks.

The nitrating and drying process is performed in the apparatus in thefollowing manner: After having closed the discharge tap C the casing Bis filled with therequired quantit'y of acid and the substance to benitrated immersed in the acid, contained in the basket A. Now theprocess is conducted in the known manner, cold or hot water flowingthrough the jacket hif required, and the exhauster being at work fordrawing off the acidvapor. AWhen the nitrating is finished the acid is'let off by opening the discharge cock C and the basket A is put inmotion for freeing the nitrated substance contained in it from theexcess of acid by centrifugal force. This having been done the basket isstopped and the nitrated substance taken out of it, for being washed inthe usual manner.

Having `now fully described my invention, what I desire to claim andsecure by Letters Patent is- A nitrating apparatus comprising the acid 5vat having a Water jacket, the centrifugal basket. journaled thereinhaving an inwardly extended flange With an upturned edge, the

cap covering the space around the basket and having its inner edgeturned over` the edge xo of the flange, the hood extending over theentire upper surface of the vat, the inlet pipe terminating over theopening in the cap, the outlet pipe and the pipe connected With thespace around the basket through an 'opening in the cap, substantially asdescribed.

JOHANNES SELWG. \Vitnesse`s:

NVM. G. SPALDING, A. HOFFENLISTER.

